[lttng-tools.git] / src / bin / lttng-consumerd / health-consumerd.c

/*
 * Copyright (C) 2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _LGPL_SOURCE
#include <fcntl.h>
#include <getopt.h>
#include <grp.h>
#include <limits.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ipc.h>
#include <sys/resource.h>
#include <sys/shm.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <urcu/list.h>
#include <poll.h>
#include <unistd.h>
#include <sys/mman.h>
#include <assert.h>
#include <urcu/compiler.h>
#include <ulimit.h>
#include <inttypes.h>

#include <common/defaults.h>
#include <common/common.h>
#include <common/consumer/consumer.h>
#include <common/consumer/consumer-timer.h>
#include <common/compat/poll.h>
#include <common/sessiond-comm/sessiond-comm.h>
#include <common/utils.h>

#include "lttng-consumerd.h"
#include "health-consumerd.h"

/* Global health check unix path */
static char health_unix_sock_path[PATH_MAX];

int health_quit_pipe[2];

/*
 * Check if the thread quit pipe was triggered.
 *
 * Return 1 if it was triggered else 0;
 */
static
int check_health_quit_pipe(int fd, uint32_t events)
{
	if (fd == health_quit_pipe[0] && (events & LPOLLIN)) {
		return 1;
	}

	return 0;
}

/*
 * Send data on a unix socket using the liblttsessiondcomm API.
 *
 * Return lttcomm error code.
 */
static int send_unix_sock(int sock, void *buf, size_t len)
{
	/* Check valid length */
	if (len == 0) {
		return -1;
	}

	return lttcomm_send_unix_sock(sock, buf, len);
}

static
int setup_health_path(void)
{
	int is_root, ret = 0;
	enum lttng_consumer_type type;
	const char *home_path;

	type = lttng_consumer_get_type();
	is_root = !getuid();

	if (is_root) {
		if (strlen(health_unix_sock_path) != 0) {
			goto end;
		}
		switch (type) {
		case LTTNG_CONSUMER_KERNEL:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_GLOBAL_KCONSUMER_HEALTH_UNIX_SOCK);
			break;
		case LTTNG_CONSUMER64_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_GLOBAL_USTCONSUMER64_HEALTH_UNIX_SOCK);
			break;
		case LTTNG_CONSUMER32_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_GLOBAL_USTCONSUMER32_HEALTH_UNIX_SOCK);
			break;
		default:
			ret = -EINVAL;
			goto end;
		}
	} else {
		home_path = utils_get_home_dir();
		if (home_path == NULL) {
			/* TODO: Add --socket PATH option */
			ERR("Can't get HOME directory for sockets creation.");
			ret = -EPERM;
			goto end;
		}

		/* Set health check Unix path */
		if (strlen(health_unix_sock_path) != 0) {
			goto end;
		}
		switch (type) {
		case LTTNG_CONSUMER_KERNEL:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_KCONSUMER_HEALTH_UNIX_SOCK, home_path);
			break;
		case LTTNG_CONSUMER64_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_USTCONSUMER64_HEALTH_UNIX_SOCK, home_path);
			break;
		case LTTNG_CONSUMER32_UST:
			snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
				DEFAULT_HOME_USTCONSUMER32_HEALTH_UNIX_SOCK, home_path);
			break;
		default:
			ret = -EINVAL;
			goto end;
		}
	}
end:
	return ret;
}

/*
 * Thread managing health check socket.
 */
void *thread_manage_health(void *data)
{
	int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
	uint32_t revents, nb_fd;
	struct lttng_poll_event events;
	struct health_comm_msg msg;
	struct health_comm_reply reply;
	int is_root;

	DBG("[thread] Manage health check started");

	setup_health_path();

	rcu_register_thread();

	/* We might hit an error path before this is created. */
	lttng_poll_init(&events);

	/* Create unix socket */
	sock = lttcomm_create_unix_sock(health_unix_sock_path);
	if (sock < 0) {
		ERR("Unable to create health check Unix socket");
		ret = -1;
		goto error;
	}

	is_root = !getuid();
	if (is_root) {
		/* lttng health client socket path permissions */
		ret = chown(health_unix_sock_path, 0,
				utils_get_group_id(tracing_group_name));
		if (ret < 0) {
			ERR("Unable to set group on %s", health_unix_sock_path);
			PERROR("chown");
			ret = -1;
			goto error;
		}

		ret = chmod(health_unix_sock_path,
				S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
		if (ret < 0) {
			ERR("Unable to set permissions on %s", health_unix_sock_path);
			PERROR("chmod");
			ret = -1;
			goto error;
		}
	}

	/*
	 * Set the CLOEXEC flag. Return code is useless because either way, the
	 * show must go on.
	 */
	(void) utils_set_fd_cloexec(sock);

	ret = lttcomm_listen_unix_sock(sock);
	if (ret < 0) {
		goto error;
	}

	/* Size is set to 1 for the consumer_channel pipe */
	ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
	if (ret < 0) {
		ERR("Poll set creation failed");
		goto error;
	}

	ret = lttng_poll_add(&events, health_quit_pipe[0], LPOLLIN);
	if (ret < 0) {
		goto error;
	}

	/* Add the application registration socket */
	ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLPRI);
	if (ret < 0) {
		goto error;
	}

	/* Perform prior memory accesses before decrementing ready */
	cmm_smp_mb__before_uatomic_dec();
	uatomic_dec(&lttng_consumer_ready);

	while (1) {
		DBG("Health check ready");

		/* Inifinite blocking call, waiting for transmission */
restart:
		ret = lttng_poll_wait(&events, -1);
		if (ret < 0) {
			/*
			 * Restart interrupted system call.
			 */
			if (errno == EINTR) {
				goto restart;
			}
			goto error;
		}

		nb_fd = ret;

		for (i = 0; i < nb_fd; i++) {
			/* Fetch once the poll data */
			revents = LTTNG_POLL_GETEV(&events, i);
			pollfd = LTTNG_POLL_GETFD(&events, i);

			if (!revents) {
				/* No activity for this FD (poll implementation). */
				continue;
			}

			/* Thread quit pipe has been closed. Killing thread. */
			ret = check_health_quit_pipe(pollfd, revents);
			if (ret) {
				err = 0;
				goto exit;
			}

			/* Event on the registration socket */
			if (pollfd == sock) {
				if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)
						&& !(revents & LPOLLIN)) {
					ERR("Health socket poll error");
					goto error;
				}
			}
		}

		new_sock = lttcomm_accept_unix_sock(sock);
		if (new_sock < 0) {
			goto error;
		}

		/*
		 * Set the CLOEXEC flag. Return code is useless because either way, the
		 * show must go on.
		 */
		(void) utils_set_fd_cloexec(new_sock);

		DBG("Receiving data from client for health...");
		ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
		if (ret <= 0) {
			DBG("Nothing recv() from client... continuing");
			ret = close(new_sock);
			if (ret) {
				PERROR("close");
			}
			new_sock = -1;
			continue;
		}

		rcu_thread_online();

		assert(msg.cmd == HEALTH_CMD_CHECK);

		memset(&reply, 0, sizeof(reply));
		for (i = 0; i < NR_HEALTH_CONSUMERD_TYPES; i++) {
			/*
			 * health_check_state return 0 if thread is in
			 * error.
			 */
			if (!health_check_state(health_consumerd, i)) {
				reply.ret_code |= 1ULL << i;
			}
		}

		DBG("Health check return value %" PRIx64, reply.ret_code);

		ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
		if (ret < 0) {
			ERR("Failed to send health data back to client");
		}

		/* End of transmission */
		ret = close(new_sock);
		if (ret) {
			PERROR("close");
		}
		new_sock = -1;
	}

exit:
error:
	if (err) {
		ERR("Health error occurred in %s", __func__);
	}
	DBG("Health check thread dying");
	unlink(health_unix_sock_path);
	if (sock >= 0) {
		ret = close(sock);
		if (ret) {
			PERROR("close");
		}
	}

	lttng_poll_clean(&events);

	rcu_unregister_thread();
	return NULL;
}
Commit	Line	Data
5c635c72 MD	1	/*
	2	* Copyright (C) 2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License, version 2 only,
	6	* as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License along
	14	* with this program; if not, write to the Free Software Foundation, Inc.,
	15	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	16	*/
	17
6c1c0768	18	#define _LGPL_SOURCE
5c635c72 MD	19	#include <fcntl.h>
	20	#include <getopt.h>
	21	#include <grp.h>
	22	#include <limits.h>
	23	#include <pthread.h>
	24	#include <signal.h>
	25	#include <stdio.h>
	26	#include <stdlib.h>
	27	#include <string.h>
	28	#include <sys/ipc.h>
	29	#include <sys/resource.h>
	30	#include <sys/shm.h>
	31	#include <sys/socket.h>
	32	#include <sys/stat.h>
	33	#include <sys/types.h>
	34	#include <urcu/list.h>
	35	#include <poll.h>
	36	#include <unistd.h>
	37	#include <sys/mman.h>
	38	#include <assert.h>
5c635c72 MD	39	#include <urcu/compiler.h>
5c635c72 MD	40	#include <ulimit.h>
6c71277b	41	#include <inttypes.h>
5c635c72 MD	42
	43	#include <common/defaults.h>
	44	#include <common/common.h>
c8fea79c JR	45	#include <common/consumer/consumer.h>
c8fea79c JR	46	#include <common/consumer/consumer-timer.h>
5c635c72 MD	47	#include <common/compat/poll.h>
	48	#include <common/sessiond-comm/sessiond-comm.h>
	49	#include <common/utils.h>
	50
	51	#include "lttng-consumerd.h"
	52	#include "health-consumerd.h"
	53
	54	/* Global health check unix path */
	55	static char health_unix_sock_path[PATH_MAX];
	56
	57	int health_quit_pipe[2];
	58
	59	/*
	60	* Check if the thread quit pipe was triggered.
	61	*
	62	* Return 1 if it was triggered else 0;
	63	*/
	64	static
	65	int check_health_quit_pipe(int fd, uint32_t events)
	66	{
	67	if (fd == health_quit_pipe[0] && (events & LPOLLIN)) {
	68	return 1;
	69	}
	70
	71	return 0;
	72	}
	73
	74	/*
	75	* Send data on a unix socket using the liblttsessiondcomm API.
	76	*
	77	* Return lttcomm error code.
	78	*/
	79	static int send_unix_sock(int sock, void *buf, size_t len)
	80	{
	81	/* Check valid length */
	82	if (len == 0) {
	83	return -1;
	84	}
	85
	86	return lttcomm_send_unix_sock(sock, buf, len);
	87	}
	88
	89	static
	90	int setup_health_path(void)
	91	{
	92	int is_root, ret = 0;
	93	enum lttng_consumer_type type;
	94	const char *home_path;
	95
	96	type = lttng_consumer_get_type();
	97	is_root = !getuid();
	98
	99	if (is_root) {
	100	if (strlen(health_unix_sock_path) != 0) {
	101	goto end;
	102	}
	103	switch (type) {
	104	case LTTNG_CONSUMER_KERNEL:
	105	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
	106	DEFAULT_GLOBAL_KCONSUMER_HEALTH_UNIX_SOCK);
	107	break;
	108	case LTTNG_CONSUMER64_UST:
	109	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
	110	DEFAULT_GLOBAL_USTCONSUMER64_HEALTH_UNIX_SOCK);
111	break;
112	case LTTNG_CONSUMER32_UST:
113	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
114	DEFAULT_GLOBAL_USTCONSUMER32_HEALTH_UNIX_SOCK);
115	break;
116	default:
117	ret = -EINVAL;
118	goto end;
119	}
120	} else {
5c635c72 MD	121	home_path = utils_get_home_dir();
	122	if (home_path == NULL) {
	123	/* TODO: Add --socket PATH option */
	124	ERR("Can't get HOME directory for sockets creation.");
	125	ret = -EPERM;
	126	goto end;
	127	}
	128
5c635c72 MD	129	/* Set health check Unix path */
	130	if (strlen(health_unix_sock_path) != 0) {
	131	goto end;
	132	}
	133	switch (type) {
	134	case LTTNG_CONSUMER_KERNEL:
	135	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
dbc8403d	136	DEFAULT_HOME_KCONSUMER_HEALTH_UNIX_SOCK, home_path);
5c635c72 MD	137	break;
	138	case LTTNG_CONSUMER64_UST:
	139	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
dbc8403d	140	DEFAULT_HOME_USTCONSUMER64_HEALTH_UNIX_SOCK, home_path);
5c635c72 MD	141	break;
	142	case LTTNG_CONSUMER32_UST:
	143	snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
dbc8403d	144	DEFAULT_HOME_USTCONSUMER32_HEALTH_UNIX_SOCK, home_path);
5c635c72 MD	145	break;
	146	default:
	147	ret = -EINVAL;
	148	goto end;
	149	}
	150	}
5c635c72 MD	151	end:
	152	return ret;
	153	}
	154
	155	/*
	156	* Thread managing health check socket.
	157	*/
	158	void thread_manage_health(void data)
	159	{
	160	int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
	161	uint32_t revents, nb_fd;
	162	struct lttng_poll_event events;
	163	struct health_comm_msg msg;
	164	struct health_comm_reply reply;
6c71277b	165	int is_root;
5c635c72 MD	166
	167	DBG("[thread] Manage health check started");
	168
	169	setup_health_path();
	170
	171	rcu_register_thread();
	172
	173	/* We might hit an error path before this is created. */
	174	lttng_poll_init(&events);
	175
	176	/* Create unix socket */
	177	sock = lttcomm_create_unix_sock(health_unix_sock_path);
	178	if (sock < 0) {
	179	ERR("Unable to create health check Unix socket");
	180	ret = -1;
	181	goto error;
	182	}
	183
6c71277b MD	184	is_root = !getuid();
	185	if (is_root) {
	186	/* lttng health client socket path permissions */
	187	ret = chown(health_unix_sock_path, 0,
	188	utils_get_group_id(tracing_group_name));
	189	if (ret < 0) {
	190	ERR("Unable to set group on %s", health_unix_sock_path);
	191	PERROR("chown");
	192	ret = -1;
	193	goto error;
	194	}
	195
	196	ret = chmod(health_unix_sock_path,
	197	S_IRUSR \| S_IWUSR \| S_IRGRP \| S_IWGRP);
	198	if (ret < 0) {
	199	ERR("Unable to set permissions on %s", health_unix_sock_path);
	200	PERROR("chmod");
	201	ret = -1;
	202	goto error;
	203	}
	204	}
	205
5c635c72 MD	206	/*
	207	* Set the CLOEXEC flag. Return code is useless because either way, the
	208	* show must go on.
	209	*/
	210	(void) utils_set_fd_cloexec(sock);
	211
	212	ret = lttcomm_listen_unix_sock(sock);
	213	if (ret < 0) {
	214	goto error;
	215	}
	216
	217	/* Size is set to 1 for the consumer_channel pipe */
	218	ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
	219	if (ret < 0) {
	220	ERR("Poll set creation failed");
	221	goto error;
	222	}
	223
	224	ret = lttng_poll_add(&events, health_quit_pipe[0], LPOLLIN);
	225	if (ret < 0) {
	226	goto error;
	227	}
	228
	229	/* Add the application registration socket */
	230	ret = lttng_poll_add(&events, sock, LPOLLIN \| LPOLLPRI);
	231	if (ret < 0) {
	232	goto error;
	233	}
	234
748b7b07 MD	235	/* Perform prior memory accesses before decrementing ready */
	236	cmm_smp_mb__before_uatomic_dec();
	237	uatomic_dec(&lttng_consumer_ready);
	238
5c635c72 MD	239	while (1) {
	240	DBG("Health check ready");
	241
	242	/* Inifinite blocking call, waiting for transmission */
	243	restart:
	244	ret = lttng_poll_wait(&events, -1);
	245	if (ret < 0) {
	246	/*
	247	* Restart interrupted system call.
	248	*/
	249	if (errno == EINTR) {
	250	goto restart;
	251	}
	252	goto error;
	253	}
	254
	255	nb_fd = ret;
	256
	257	for (i = 0; i < nb_fd; i++) {
	258	/* Fetch once the poll data */
	259	revents = LTTNG_POLL_GETEV(&events, i);
	260	pollfd = LTTNG_POLL_GETFD(&events, i);
	261
fd20dac9 MD	262	if (!revents) {
	263	/* No activity for this FD (poll implementation). */
	264	continue;
	265	}
	266
5c635c72 MD	267	/* Thread quit pipe has been closed. Killing thread. */
	268	ret = check_health_quit_pipe(pollfd, revents);
	269	if (ret) {
	270	err = 0;
	271	goto exit;
	272	}
	273
	274	/* Event on the registration socket */
	275	if (pollfd == sock) {
03e43155 MD	276	if (revents & (LPOLLERR \| LPOLLHUP \| LPOLLRDHUP)
03e43155 MD	277	&& !(revents & LPOLLIN)) {
5c635c72 MD	278	ERR("Health socket poll error");
	279	goto error;
	280	}
	281	}
	282	}
	283
	284	new_sock = lttcomm_accept_unix_sock(sock);
	285	if (new_sock < 0) {
	286	goto error;
	287	}
	288
	289	/*
	290	* Set the CLOEXEC flag. Return code is useless because either way, the
	291	* show must go on.
	292	*/
	293	(void) utils_set_fd_cloexec(new_sock);
	294
	295	DBG("Receiving data from client for health...");
	296	ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
	297	if (ret <= 0) {
	298	DBG("Nothing recv() from client... continuing");
	299	ret = close(new_sock);
	300	if (ret) {
	301	PERROR("close");
	302	}
	303	new_sock = -1;
	304	continue;
	305	}
	306
	307	rcu_thread_online();
	308
	309	assert(msg.cmd == HEALTH_CMD_CHECK);
	310
53efb85a	311	memset(&reply, 0, sizeof(reply));
6c71277b MD	312	for (i = 0; i < NR_HEALTH_CONSUMERD_TYPES; i++) {
	313	/*
	314	* health_check_state return 0 if thread is in
	315	* error.
	316	*/
	317	if (!health_check_state(health_consumerd, i)) {
	318	reply.ret_code \|= 1ULL << i;
	319	}
5c635c72 MD	320	}
5c635c72 MD	321
6137f630	322	DBG("Health check return value %" PRIx64, reply.ret_code);
5c635c72 MD	323
	324	ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
	325	if (ret < 0) {
	326	ERR("Failed to send health data back to client");
	327	}
	328
	329	/* End of transmission */
	330	ret = close(new_sock);
	331	if (ret) {
	332	PERROR("close");
	333	}
	334	new_sock = -1;
	335	}
	336
	337	exit:
	338	error:
	339	if (err) {
	340	ERR("Health error occurred in %s", __func__);
	341	}
	342	DBG("Health check thread dying");
	343	unlink(health_unix_sock_path);
	344	if (sock >= 0) {
	345	ret = close(sock);
	346	if (ret) {
	347	PERROR("close");
	348	}
	349	}
	350
	351	lttng_poll_clean(&events);
	352
	353	rcu_unregister_thread();
	354	return NULL;
	355	}